CLINICAL MANIFESTATIONS

The signs and symptoms of osteoarthritis depend on the joint or joints affected (see Plate 5-22). Most commonly involved are the weight-bearing joints (see Plate 5-23) and small joints of the hand.

Pain and restricted movement are the major clinical manifestations. The patient is usually comfortable at rest but finds weight bearing and moving the affected joints painful. Aching during rainy weather, stiffness after inactivity, and crepitation are other frequent complaints.

Physical examination reveals tenderness, pain and crepitation with joint movement, and, usually, a limited range of motion. Although signs of synovitis—warmth and erythema over the joint—are usually limited or absent, swelling exists in association with bony hypertrophy or if there is a joint effusion.

Knee Joint Involvement

Of the large joints, the knee is most often affected. Because the knee is so crucial in the lever action of the leg and in ambulation, osteoarthritis in this joint can be both very painful and disabling, especially when it is bilateral (see Plate 5-24). The medial compartment of the knee is usually more severely damaged than the lateral compartment. The structural damage in the joint causes pain, restriction of motion, and crepitation. Subluxation and angular deformities are late sequelae.

Hand Involvement

Some clinical manifestations are unique to particular joints. Heberden’s and Bouchard’s nodes, hallmarks of osteoarthritis, develop at the distal and proximal interphalangeal joints of the fingers (see Plate 5-25). Although the cartilage of the distal and proximal interphalangeal joint is degenerating, osteophytes grow from the dorsomedial and dorsolateral aspects of the base of the distal phalanx to produce these nodular protuberances. Flexion deformity may occur when the pathologic changes are severe. Early in their development, the nodes are tender and painful; when mature, they are often asymptomatic but may have significant cosmetic effects. Heberden’s nodes are more common in women and are often familial. Bouchard’s nodes, similar to but less common than Heberden’s nodes, develop at the proximal interphalangeal finger joints.